This invention relates to reels for winding and unwinding line for lowering and raising window shades, curtains and blinds without entanglement of the line.
A conventional practice of raising and lowering horizontally pleated shades, curtains and Venetian-like blinds on shaft-like reels has been fraught with problems of entanglement and bunching of the line by minor interferences. There are known devices and methods for preventing line entanglement and bunching but not with a simple and effective line-reeling controller in relationship to select shades, curtains and blinds in a manner taught by this invention.
There is no known screw-threaded reel for linear actuation to prevent bunching in a manner taught by this invention.
Examples of most-closely related known but different devices are described in the following patent documents:
Objects of patentable novelty and utility taught by this invention are to provide a motorized reel system for window covering which:
is reliably operative;
does not cause reel lines or strings to slide toward tapered ends as for present tapered reels;
can be used for unusually small-to-large sizes of shades;
prevents strings from becoming entangled;
can be used on a wide variety of lengths and sizes of reel-rail heads;
can use a wide variety of motors; and
does not need a duplicate mounting bracket.
This invention accomplishes these and other objectives with a motorized reel system for window covering having a reel case with a length for reaching between opposite sides of a window frame. The reel case encloses a reel motor in a first end and a reel housing in a second end. The reel motor is attached to a motor base having a reel slide in which a first end of a shaft-like reel slides linearly in one direction while the shaft-like reel is also winding lift line. The shaft-like reel slides linearly in the opposite direction while the shaft-like reel is unwinding the lift line. Linear sliding of the shaft-like reel while also winding and unwinding the lift line is caused by rotation of outside-diameter threads in a second end of the shaft-like reel that match inside-diameter threads in the reel housing. Linear travel of the shaft-like reel while it is being rotated prevents overlapping and bunching of one or more lift lines being reeled onto and off of the shaft-like reel while raising and lowering bottom ends of window shade, curtain Venetian-like blinds or other window covering having pleating or other foldable features.
The above and other objects, features and advantages of the present invention should become even more readily apparent to those skilled in the art upon a reading of the following detailed description in conjunction with the drawings wherein there is shown and described illustrative embodiments of the invention.